From: Nathan Chancellor natechancellor@gmail.com
[ Upstream commit e898e69d6b9475bf123f99b3c5d1a67bb7cb2361 ]
When building with -Wsometimes-uninitialized, Clang warns:
arch/x86/kernel/hw_breakpoint.c:355:2: warning: variable 'align' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
The default cannot be reached because arch_build_bp_info() initializes hw->len to one of the specified cases. Nevertheless the warning is valid and returning -EINVAL makes sure that this cannot be broken by future modifications.
Suggested-by: Nick Desaulniers ndesaulniers@google.com Signed-off-by: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Nick Desaulniers ndesaulniers@google.com Cc: Borislav Petkov bp@alien8.de Cc: "H. Peter Anvin" hpa@zytor.com Cc: clang-built-linux@googlegroups.com Link: https://github.com/ClangBuiltLinux/linux/issues/392 Link: https://lkml.kernel.org/r/20190307212756.4648-1-natechancellor@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/hw_breakpoint.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c index 34a5c1715148..2882fe1d2a78 100644 --- a/arch/x86/kernel/hw_breakpoint.c +++ b/arch/x86/kernel/hw_breakpoint.c @@ -357,6 +357,7 @@ int hw_breakpoint_arch_parse(struct perf_event *bp, #endif default: WARN_ON_ONCE(1); + return -EINVAL; }
/*